: John, did you find this through normal gameplay, or did you sneak a peak
: and notice the differing poly type on that trigger?
The first time I played, I honestly think the sequence of events went like this. I hopped onto that ledge hoping it would open some door to get me out of this nightmare part of the level. Later I noticed that the door leading to the 3rd overlook was open. Of course, I had no idea what had triggered it. After finishing the level I checked in Pfhorte to see if I had collected all ammo. That's when I noticed that the ledge triggers that door. It's a sneaky secret. Not sure I would have thought to jump on it if I had not been so desperate for a way to leave that section of the level. I suppose it teaches us one lesson: If you can jump on top of it, then do it. You never know what it might do. :)